I have a R1208GZ4GC Server System, I would like to install 8 2.5" SSD SAS drives on an add-in controller. Any time that I install more then 5 disks and start the server all the installed drives blink amber and no drives will be detected. I've check all my drives in another system and all is well, I can install any 5 drives in any slot and it always works, but if I install 6 or more it doesn't. The full active power requirements for the disks is 7.4w according to the manufacturer, and the server has redundant 740w PS. I'm not sure as to what to do next? Any suggestions?

No the disks I am using are not listed on the server configurator, but the the RAID controller is. It's not a problem with the controller tho, I get the same results with the integrated, and also the same amber blinking error on the hard disk when the backplane is not even plugged into a controller.